[tracing] Fix single-process detection logic of ChildTraceMessageFilter

content/child/child_thread_impl.cc

Index: content/child/child_thread_impl.cc
diff --git a/content/child/child_thread_impl.cc b/content/child/child_thread_impl.cc
index 013d1d51302d1920edcbe76ec7b463357789c8f5..62518ea2ee60f5b9c63fcda1e6218978293a9c9c 100644
--- a/content/child/child_thread_impl.cc
+++ b/content/child/child_thread_impl.cc
@@ -401,8 +401,7 @@ void ChildThreadImpl::Init(const Options& options) {
   channel_->AddFilter(bluetooth_message_filter_->GetFilter());
   channel_->AddFilter(navigator_connect_dispatcher_->GetFilter());
 
-  if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kSingleProcess)) {
+  if (!IsInBrowserProcess()) {
     // In single process mode, browser-side tracing will cover the whole
     // process including renderers.
     channel_->AddFilter(new tracing::ChildTraceMessageFilter(